The effect of ethnicity on left ventricular adaptation to exercise

Ethnicity is a major determinant of cardiac adaptation to exercise. Black athletes (BAs) demonstrate more profound electrical and structural changes than white athletes (WAs), which manifest on the 12-lead electrocardiogram (ECG) and echocardiogram.1,2 It is well established that BAs develop greater left ventricular hypertrophy (LVH) in response to exercise, compared to WAs, creating a larger overlap between physiology and hypertrophic cardiomyopathy (HCM). The issue is further compounded by the fact that BAs are at increased risk of exercise-related sudden cardiac death (SCD) with HCM accounting for a significant proportion of cases.3 The growing number of elite black sportsmen and women has intensified efforts to correctly identify those at risk. Left ventricular (LV) geometry has been postulated as a more accurate tool compared to absolute LV wall thickness in differentiating physiological LV hypertrophy from HCM. Although LV geometry has been well characterized in WAs,4 there is a paucity of data in male BAs and even less data in female BAs. This study aimed to establish the influence of black ethnicity on LV geometry and to derive ethnicity-specific normative values for relative wall thickness (RWT).